Numerical Calculation of Thermal Discharge by Power Station in Tidal Estuary using Curvilinear Body-Fitted boundary

In view of coal transportation and the demand of water source, more and more large of thermal (nuclear) power station will be built in the estuary and nearshore area where water hydrodynamics factors are complicated. It is important to forecast accurately the process of inlet-intaken temperature deficiency for the normal operation and safe fully-loaded generating electricity of the plant. In addition, the estuary and nearshore areas are also the important places of human activity. The influence on environmental water body and aquatic ecology by thermal discharge of power plant is paid close attention by environmental protection and fishery production administration, thus, the numerical forecasting of the process of inletintake temperature deficiency and influence extent on receiving water body by thermal discharge of plant is an important research content in the engineering feasibility and environmental evaluation. In many computational models of thermal discharge, the difference model in the Cartesian coordinate system is widely adopted currently. This model has the advantage of good stability and less necessary memory capacity, however , the simulated boundary fits poorly with the real one, and it also confines the distribution of grid points. Countering the above difficulty, the body fitted boundary system has been developed and applied in the computation of flow field recently. In this paper, usual Poisson equation is improved, then body fitted boundary is generated. the simulated boundary fits well with the real one; the interval between relative grids can also be adjusted according to the demand. This model can also be conveniently apply to the computation of thermal discharge.